GAI-Tronics IPE2500A, User And Installation Manual

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Description IPE2500A and IPE2500A-MLS Paging Encoder/Desktop Controller
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Control Tones
Standard EIA tone keying tones are used for controlling the radio system. The sequence is:

A 2175 Hz High Level Guard Tone (HLGT) for 120 ms (default), programmable via CARD Suite.

One of 16 function tones (FT) is sent for 40 ms (default), programmable via CARD Suite.
The frequency range is from 2050 Hz to 550 Hz in 100 Hz steps. The FT level is 10 dB lower than
the HLGT.
Monitor/F16 2050 F4 1650 F8 1250 F12 850
F1 1950 F5 1550 F9 1150 F13 750
F2 1850 F6 1450 F10 1050 F14 650
F3 1750 F7 1350 F11 950 F15 550

A 2175 Hz Low Level Guard Tone (LLGT) is generated for the duration of the transmission. The
LLGT is not generated during monitor. Because voice is present with this LLGT, a 2175 Hz filtering
is required in the tone panel.
When the monitor (CTCSS disable) is activated, the HLGT is generated for 120 ms, then a function
tone of 2050 Hz is generated for 40 ms.
Tone Levels
Assuming that the ITA2000A Tone Remote Adapter has the HLGT output level set to 0 dBm:

The FT level and audio voice level are –10 dBm (10 dB below HLGT)

The LLGT level is –30 dBm.

The HLGT and FT durations are programmable.
Some tone panels use the value of the FT frequency to provide certain radio control functions. If the
radio supports channel changes from an external logic source, the FT1 frequency of 1950 Hz could be
used to change the radio to channel 1. An FT6 frequency of 1450 Hz could change the radio to
channel 6. This operation is identified as “channel steering.”
DTMF Decode/H.E.A.R. System Support
The IPE2500A will decode incoming DTMF and display the ID numerically or as a preprogrammed
alias. The DTMF decode function will provide H.E.A.R. system support using a base ID DTMF code to
perform speaker un-muting and alert functions.